Fabrication of a stable Ti/TiOxHy/Sb−SnO2 anode for aniline degradation in different electrolytes

Abstract

A novel anode Ti/TiOxHy/Sb−SnO2 with excellent oxidation ability and long lifetime was successfully fabricated by introducing a TiOxHy interlayer through a simple way. The Ti substrate was modified through thermal oxidation followed by an electrochemical reduction process. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), accelerated lifetime test, scanning electron microscope (SEM) and X-ray diffraction (XRD) were adopted to characterize its morphology, crystal structure and electrochemical properties. These studies indicated that TiOxHy interlayer played a critical role in improving electrode stability. Besides, the electrochemical oxidation of aniline in the NaCl and Na2SO4 were both investigated to test the application of this Ti/TiOxHy/Sb−SnO2 electrode. Results showed that nearly 70% of aniline could be degraded within 2h. After characterization of the intermediates and products, a possible electrochemical degradation mechanism of aniline was proposed. It was worth noting that due to electro-polymerization, some nonconductive oligo(aniline)s could accumulate on the anode surface and lower the oxidation ability of the anode. However, the anode could be recovered repeatedly (at least 5 times) by essential electrochemical activation process, which also relied on the high electrode stability.